1. Field of the Invention
The present invention relates to a device for preventing the jutting-out of the ladder of a ladder truck. More particularly, in a ladder truck equipped with an extensible ladder of the type in which several stage ladders in the upper stages are successively withdrawn from the stage ladders in the lower stages by a wire rope to extend them and in which the retraction of the stage ladders is effected by unwinding said rope with extensible ladder erected so as to allow the stage ladders to be retracted under their own weight, if the truck running with the extensible ladder retracted and lying flat is suddenly braked, said several stage ladders in the upper stage will jut out by inertia. The present invention is intended to prevent such jutting out.
2. Description of the Prior Art
The conventional jutting-out preventing device comprises an L-shaped lever pivotally mounted on a ladder support on a truck frame so that when the ladder is prostrated onto the ladder support, the lower surface of the ladder abuts against and depresses one arm of said lever to turn the lever under the weight of the ladder until the other arm swings upwardly through an opening defined by ladder crosspieces into abutment against the front side of a row of crosspieces of the superposed stage ladders to prevent jutting out. According to this device, if the stage ladders are completely retracted, there will be no problem since the fixedly spaced ladder crosspieces are then vertically aligned in horizontally spaced rows, but if the retraction of the stage ladders is incomplete, the ladder crosspieces are then not vertically aligned, so that there is no problem of the projecting crosspieces being broken by the lever arm, making it impossible to prevent jutting out.